What is SAN Storage? | Glossary

SANs use four common protocols to transport data:

1. Fibre Channel Protocol (FCP) – Widely adopted, FCP uses the fibre channel network to send SCSI commands. It provides high-speed delivery of raw block data with no losses between computer storage and servers.

2. Internet Small Computer System Interface (iSCSI) – Used by about a tenth of enterprises, iSCSI has a lower cost than FCP. iSCSI maps block-oriented storage data using SCSI commands inside an Ethernet frame and then uses a standard TCP/IP Ethernet network for transport.

3. Fibre Channel over Ethernet (FCoE) – FCoE essentially places the FCP on a new physical link—an Ethernet link. Because of that simple switch, a SAN can use less hardware and cabling, with easier installation and management than traditional protocols. It is a standards-based protocol that also eliminates the need to run separate LAN and SAN networks.

4. Non-Volatile Memory Express Over Fibre Channel (FC-NVMe) – FC-NVMe is an interface protocol for accessing flash storage via a PCI Express (PCIe) bus. FC-NVMe offers vast performance improvements over traditional all-flash architectures (AHCI). While AHCI are limited to a single, serial command queue, NVMe can handle tens of thousands of parallel queues, each managing tens of thousands of simultaneous commands.